Monday morning.
We left home a little earlier than usual and made our way to our usual convenience store. We had a different meeting arrangement today than we normally did.
Hanasaki-san had reached out last night, saying she wanted to join us on the commute starting today. I thought she might already be there since we were early... and sure enough, as I walked, I spotted two figures standing in front of the store.
One was, of course, Natsumi-senpai.
Standing beside her was the "Big Sister" whose distinctive, fluffy twin-tails would likely make her a massive hit with fans of that particular niche(?).
Yes, it was Hanasaki-san.
Noticing our arrival, they waved and began walking slowly toward us.
"Morning."
"Mornin', you two!"
Natsumi-senpai seemed to be in exceptionally high spirits; her energy was much higher than usual. I suspected this was the influence of her finally becoming lovers with Yuji. The reality of it had probably started to sink in.
"Good morning~"
"Good morning. Natsumi, you seem to be in a remarkably good mood today."
"I-I don't think that's the case... I'm the same as always."
Natsumi-senpai replied with a hint of fluster after Sara-san pointed it out. To any outside observer, her energy was clearly anything but "same as always," but was she really unaware of it herself?
"I don't know what you're trying to hide... but you're not doing a very good job of it, are you?"
Hanasaki-san, who was in the dark about the circumstances, seemed to feel the same way I did. She looked at Natsumi-senpai with a slightly deadpan expression.
"Ahaha... Well, yeah, a little. I knew I had to give a report eventually, so I'll talk about it during lunch break."
Looking at her now, even if she tried to stay silent, the group would undoubtedly press her for the truth. Natsumi-senpai was weak when it came to being teased, so the report was only a matter of "sooner or later." Besides, even if she spoke during lunch, she would likely end up reporting the news to everyone in Group RAIN anyway.
"...I see. I think I have a rough idea. Did Tachibana-kun confess to you?"
"Wha!?"
Hanasaki-san’s intuition was as sharp as ever. Given Natsumi's unusual behavior and the mention of a "report," it wasn't hard to guess. Since Sara-san and I had just held a debriefing session the other day, she might have made the connection from that.
"I see. I thought it would take a bit more time, so I'm a little surprised. But, congratulations."
"Ahaha... thanks. I guess it was that obvious?"
"Of course it was. Well, I'll wait until lunch break for the details."
As Hanasaki-san spoke with a pleasant smile, Natsumi-senpai seemed to grow curious about her friend's demeanor in turn. After observing her for a moment, Natsumi-senpai seemed to catch onto something and wore a meaningful, mischievous grin.
"Hmm... Did something happen on your end too, Hanasaki-san?"
Until now, Hanasaki-san's default style had been "blunt," and she rarely ever smiled during daily conversation. For anyone who knew her, noticing the change in her vibe wasn't particularly difficult.
"I have nothing to hide. Kazunari simply became my younger brother. That makes me happy."
Casting a quick glance toward me, Hanasaki-san smiled brightly. For my part, I was sincerely glad to see my best friend showing such positive change. However, her tendency to be overly brief with words hadn't changed at all, which meant there was always a risk of her being misunderstood. It felt like we were in the middle of one of those moments right now...
"Huh? W-What? Younger brother?"
"Yes. Since we're at it, I'll talk about it at noon as well. I should report that I became Kazunari's Big Sister, and I don't want to cause trouble for the wife through any weird misunderstandings."
I was grateful that Hanasaki-san was willing to explain herself. If she was going to act as my sister from now on, there was a high possibility of inviting unnecessary rumors unless she set the record straight with everyone. That would ultimately lead to trouble for Sara-san, and it seemed Hanasaki-san had been thoughtful enough to consider that.
"I see. It sounds complicated, so we'll need a solid explanation. But putting the Big Sister title aside, won't Sara get mad if you address Takanashi-kun without honorifics? Right, Sara?"
"...To be honest, it isn't as if I don't have my own thoughts on the matter. However, I have already been granted a special way to address him, after all."
This undoubtedly referred to her calling me "Darling." As long as it made Sara-san happy, I naturally had no problem with it. To be perfectly honest, though, I wasn't used to being called that in public yet, and it was still way too embarrassing. Incidentally, if I gave the wrong response to that name, a punishment disguised as a reward would be waiting for me.
"Heh... What is th— Oh, I see. That was the reason for what happened yesterday."
Natsumi-senpai must have recalled the scene at the cafe. Since Sara-san had called me "Darling" right in front of them, it was only natural for her to put the pieces together. Perhaps because they had been preoccupied with their own situation at the time, they hadn't pressed us for details then.
"Fufu..."
"Guh... that composure of yours is bothersome."
With Sara-san conspicuously flaunting her composure, Hanasaki-san seemed increasingly irked. It almost looked like they were locked in some kind of silent competition.
"Heh... Takanashi-kun is a lucky guy, isn't he?"
"Y-Yes, I suppose so."
Meanwhile, I was being subjected to Natsumi-senpai's Scornful Look Attack. For now, I would just have to ride this out with a forced smile and hope Hanasaki-san's explanation during lunch break would satisfy them. If her brevity caused more confusion, I would have to follow up on her behalf as a last resort.
"Morning."
"Morning, Takanashi-kun."
"Hey."
Entering the classroom, I exchanged brief morning greetings as I headed to my seat. The gazes of my classmates, which had been normal until now, suddenly began to gather behind me.
Behind me was, of course, Hanasaki-san.
When I thought about it, she had always arrived at school alone before me until today. Entering the classroom together made the situation obvious, and it immediately piqued their interest.
The moment we sat down, we were surrounded by the usual group of girls.
"Hanasaki-san, you came with Takanashi-kun today!"
"Hehe, as close as ever, aren't you?"
"If anything, you're so close that there's no room for anyone else to get between you two."
I didn't intend to deny that we were on good terms, but their phrasing felt... a bit suggestive, to say the least.
I had thought they would be satisfied after Yamakawa and the others cleared up the previous misunderstandings.
"It's only natural for a Big Sister and younger brother to get along."
""" Eh?? """
Apparently, Hanasaki-san intended to act as my sister even in the classroom.
Since I had Sara-san, I didn't care what my classmates thought of me, but I should probably tell her later to spare me the embarrassment of actually calling her "Big Sister" out loud...
"Eh... Big sister?"
"W-What do you mean by that?"
"Exactly what it sounds like. Because I am his Big Sister."
"Um?"
Since she was as short on words as ever, I thought I should probably step in and explain things a bit more clearly. But just as I was about to join the conversation, one of the girls seemed to realize something and whispered to the others.
"...Look, in other words, the two of them are using that setting... to flirt..."
"Ah!! So that's it!"
"I see, it's that kind of vibe."
It seemed they had reached their own conclusion without me saying a word. They appeared to accept it more easily than I expected; girls really were highly adaptable when it came to these things.
"Got it. So, Hanasaki-san is using a Big Sister Setting, right?"
"Mu... It's not a setting. I am his Big Sister."
Displeased with her phrasing, Hanasaki-san frowned and argued back.
But the fact that the word "setting" had even come up meant that they had understood the gist of the situation from her explanation.
"Ahaha, sorry."
"Yeah, we get it now."
"Takanashi-kun, you're lucky to have such a nice Big Sister, aren't you?"
"Eh? Y-Yeah, I guess."
I was a bit flustered by the sudden shift in focus, but Hanasaki-san smiled happily upon hearing my reply. If she could show this kind of expression more often, the day she finally moved past her trauma might not be that far off.
"...Th-That appearance with a 'Big Sister' persona... it's too much of a reward."
"...Guh... I shouldn't have a maternal fetish, and yet..."
"...I actually want to be babied by Hanasaki-san."
"...Hey, you, how old are you!?"
And the guys who were staring intently at Hanasaki-san seemed to be giving off a very different, much weirder atmosphere than usual...
Lunch break.
We were chatting while eating our bentos, but the conversation eventually shifted to Natsumi-senpai and Hanasaki-san.
Now that the time was right, Natsumi-senpai started by reporting that she had officially started dating Yuji.
"Hehe, I've been curious about Yuzuki-senpai and Tachibana-kun for a while, so I was worried. I'm so glad for you both!!"
"Th-Thanks. ...By the way, were we really that easy to read?"
It seemed Natsumi-senpai truly lacked any self-awareness.
Sara-san and I had known for a long time, but even without our intuition, it was obvious. She was unusually affectionate toward Yuji, and it was plain to see that Natsumi-senpai was the one proactively involving herself with him. Besides, I felt like Yuji himself was always happy to be swept up in her pace.
"Tachibana-kun aside, I think Yuzuki-senpai was very easy to read!"
"Ugh..."
"I noticed pretty much immediately that Natsumi-senpai liked Yuji."
"Guh..."
"The only one who thought it wasn't noticed was you, Natsumi."
"Gha...!"
"By the way, Kazunari-san and I have known for quite a while, but Eri and Tachikawa-san surely noticed as well."
"Ev-Everyone noticed!? I... I'm..."
As expected, she really believed she had been subtle. Having everyone point it out in rapid succession was the final blow; Natsumi-senpai slumped her shoulders, looking thoroughly dejected.
"Then, before we run out of time, I'll report too."
Leaving the dispirited Natsumi-senpai aside, Hanasaki-san announced that it was her turn. Since the class had accepted the story well enough, it shouldn't be an issue for this group.
"I became Kazunari's Big Sister. The end."
"Hey!!"
"Just kidding."
I couldn't tell if she was being serious or just playing around, but I reflexively gave a loud retort to Hanasaki-san's "joke." Hanasaki-san seemed to find my reaction amusing and giggled... who does she think made me do that?
But everyone else seemed more interested in Hanasaki-san's playful behavior than my retort.
"Sorry, I'll speak properly."
Once her laughter subsided, Hanasaki-san finally began to speak. That said, she was basically just recounting what had happened on Saturday.
She started with the fact that she had a real younger brother, her imagining an ideal version of him, her projecting that image onto me... and explained up until the point we became step-siblings.
Hanasaki-san was not a skilled communicator, to say the least. Even so, it was clear she was putting everything she had into telling the story, and because everyone sensed that, they listened in respectful silence.
"I see... so that was the reason. To be honest, I thought Hanasaki-san liked Kazunari and just hadn't realized it herself."
"Yeah, I also thought that maybe Hanasaki-san liked Takanashi-kun..."
To be honest, I thought Hanasaki-san was just getting along with me as a Best Friend. It seemed everyone else had been seeing something else entirely...
"I am his Big Sister, so talk about that kind of thing with the wife."
"I see, I understand."
"Yeah, I can see how happy Hanasaki-san is just by looking at her."
"Right. Well, as long as the people involved are satisfied, it's not our place to interfere."
Everyone seemed convinced.
The people who weren't here would surely be fine too, and all that mattered now was for her to prioritize her promise not to cause trouble for Sara-san.
"I have spoken properly with Kazunari-san, so it's all right," Sara-san said.
"On my end, I've also made it clear that we won't be doing anything out of the ordinary," I added.
"I am happy just that you acknowledged it. All that's left is for Kazunari to call me 'Big Sister,' then I'll have nothing more to say."
That might sound simple, but it was actually a very high hurdle. The reason was simple: it was incredibly embarrassing.
However, since we had made a promise, I figured I could call her that on special occasions. Like her birthday, for instance...
"Umm... is Satsukawa-senpai really okay with this?"
To be honest, I shared Todo-san's concern. Sara-san said she was fine, but I didn't know if she was truly satisfied deep down. However, if I knew Sara-san would be happy because there was something special that surpassed a "Big Sister," then I should make sure to say it myself.
"Sa... Sara, if you feel even slightly unhappy about it, I want you to tell me."
"!?"
She clearly hadn't expected me to speak up like that. Sara-san looked stunned for a moment, but eventually, a very happy smile spread across her face.
Even though it was only a single sentence, it required far more courage than I had imagined. I was honestly at my limit.
"Yes. Understood... Darling♪"
"...Wh-What was that just now..."
"...They're like a married couple... Satsukawa-senpai looks so happy."
"S-So unfair. If that's okay, I want to be called Big Sister too!"
"Fufu... because I am special."
My effort was worth it; Sara-san was clearly overjoyed.
It went without saying that Sara-san was the only "special" one for me, but I would continue to do my best so that she could truly feel it herself, every single day.